9. The air

The state of the biosphere – the air

I only want to dwell on a couple of issues in this chapter, global warming and air pollution from sources other than the greenhouse gases.

Global warming

Most of you will have heard of global warming, or “climate change”, as it has been euphemistically called. Most of you believe it is happening, and also that humanity is causing it.

So far as polls can tell us, about three-quarters of the world’s population accept that climate change is real, and over half see it as a serious threat[i]. But there is a very clever industry of scepticism and doubt which seems to prevent or slow us in acting on it (much more on this in later chapters).

One of the points of this website is that “it’s not just about climate change”. Yes, climate change is the canary in the mine. But it is human actions and behaviour as a whole which is putting us at risk, and the problem is manifesting itself in all parts of the planet – on the land, in the water, in the air, and in life itself.

So, whether you believe in climate change or not, and whether or not you believe it is caused by humanity, do not let this particular doubt blind you to ALL the things that are happening as a result of human activity, and putting our foothold on the planet at risk.

The next few paragraphs are built on the consensus views of the Intergovernmental Panel on Climate Change (IPCC), other research, and my own observations.

The air is warming up, just as the oceans are. 2016 was the warmest year on record (ie since 1880) for both, breaking the records set in 2015, which itself showed a sharp rise from the previous record year – 2014. Nine of the ten warmest years on record have occurred since 2001.

The warming is happening fast, and speeding up. Each IPCC report paints a gloomier picture than the one before it. And the science in the reports both requires very high levels of certainty, and is also always a few years behind their publication. So the odds are high that things are even worse than painted.

This is having immediate impacts on sea levels, local temperature records, glacier melting rates, and air pollution[iii]. And the link between emissions of carbon and methane (the main “greenhouse gases”) and global warming looks pretty self-evident.

Extreme weather events are increasing in number. Climate change science can’t say that the events themselves are caused by global warming but it can say with great certainty that their intensity is increased by it[iv]. The extreme weather events are a natural consequence of the turbulence caused by greater warmth of the atmosphere.

The warmer temperatures are not only warming the air and the ocean, they are also expanding the world’s dry and semi-arid zones – a basic prediction of climate science. A recent study published in the journal Nature concluded that, “About 5.7% of the global total land area has shifted towards warmer and drier climate types from 1950-2010”[v]. This drying out of the land compounds its degradation by human use, in particular by industrial agriculture, as explored in chapter 7.

The Earth’s climate is a vast complex system, acted on by a wide range of forces including the earth’s rotation, sun activity, ocean temperature, and new substances introduced into it. Two of the characteristics of natural, complex systems are unpredictability and “emergence” – new states or subsystems or things emerge.

This is why weather forecasting gets less and less accurate the further removed from a location and point in time it is – the climate as a whole is unpredictable, and the specific events that occur in it are unpredictable. So, while we know that hurricane season will probably bring numbers of hurricanes, their exact nature, timing and scale is beyond our capacity to predict.

Large complex systems are also often very resilient – that is, they are capable of handling stressors and outside influences without being damaged beyond repair or changed into a new state. When large systems come under stress, if their resilience is insufficient, they can be tipped out of their current state into a new one. “Tipping points” is an expression of this possibility.

The earth’s climate has changed abruptly and dramatically many times in the past 5 billion years. It has gone past tipping points into new states – warmer, colder, more turbulent and less, more oxygenated and less. We have some ideas about what has caused some of the previous changes. But we have no idea how close we might be to a climate tipping point in our current position, other than that the changes which are happening now are consistent with previous dramatic changes.

And we’re also unsure of how fast we might be moving towards a tipping point. Not only on our current “known” trajectory of carbon and methane release, but also through possible sudden events. The risks are increasing all the time of catastrophic events such as rapid ocean level rise caused by a massive Greenland or Antarctic glacial “spill” into the ocean, or rapid increases in greenhouse gasses cause by massive releases of methane from Arctic sub-strata or permafrost as a result of rapid heating of the (north) polar region[vi].

What is clear is that we’ve had 12,000 years of climate stability, and the numbers are showing us moving more and more rapidly out of the previously stable range.

Planetary Boundary 1 – climate change – yellow zone: This Boundary has already been used as an example, in chapter 7. To reiterate, the critical measure is CO2 concentration in the atmosphere. The safe inner limit is assessed as 350 parts-per-million (ppm) of CO2, which is also linked to a likely temperature increase of no more than 2 degrees this century. The dangerous outer limit, after which all bets are off about climate stability, sea level rises, and global temperature increases, is 450ppm.

The level is currently at about 400ppm, is going up at about 2-3ppm each year, and accelerating. That’s an absolute outer limit of 25 years before we’ve at least badly damaged, and probably pretty much destroyed, our foothold on the Earth.

This is not a problem to be addressed “later in the century” – it is a problem we need to address, vigorously, now. And this is why so much energy was put into influencing events such as the Paris climate Conference of Parties of December 2015 (COP21).

Many judged that conference a success, but it was at best a first step. It will not lead directly to the necessary reduction in CO2 concentration. Analysis of country pledges show that they fall well short of what is required to keep global warming below 2 degrees above pre-industrial levels (which was generally accepted as the “viable target”, and confirmed at the conference), let alone 1.5 degrees (set as an aspirational target at the conference), by the end of this century[vii]. By the end of 2015, we were already over half-way to the 2 degree “target”, as the graph above illustrates.

New Zealand has been a laggard on climate change issues, for various reasons, in particular its high level of energy production from hydro-electric sources (making us a bit too smug), and its high reliance on methane producing dairy cattle for wealth (making us a bit too defensive).

The previous government (2009-2017) pretty much denied climate change, and supported oil exploration and growth of industrial agriculture. Its proposal for the 2015 Paris climate conference, an 11% decrease from 1990 levels in net greenhouse gas emissions by 2030, actually represents a 23% increase in gross emissions. We were going to use our affluent country privilege to trade our way out of the problem, it appeared.

With the recent election of a more environmentally conscious government (supported by New Zealand’s Green Party), there are signs that New Zealand’s approach to climate change will improve, but how much remains an open question.

Volumes have been written about global warming, and the brief summary above scarcely does them justice. But I hope that it illustrates both the true severity and also the immediacy of the problem. I will return to the question of why the urgency of the problem has been understated in chapter 18, which discusses the impact of the “Merchants of Doubt”, and in chapter 23, which discusses the “problem of consent”.

Other forms of air pollution

Turning now to other forms of air pollution. This has been briefly mentioned in the section on land.

I first travelled outside New Zealand in the northern summer of 1976. My wife Judith and I took a trip to the United Kingdom via Los Angeles to visit family and see the sights.

My first strong impression of the United States came when we went through immigration in Hawaii. Tall, beautiful women in hot-pants walked up and down the slow queues in the stifling heat, repeating something like, “Please have your entry documents and your passports ready” in good American English. When I asked one of them where the toilets were, she smiled at me and said, “Please have your entry documents and your passports ready”.

My second strong impression came when we were approaching the mainland in the mid-afternoon. There was a long dirty yellow streak on the horizon which turned out to be the air above Los Angeles. It was visible from the outside and it was visible when we were inside it. This was the combined effect of car emissions and industrial production.

The United States has cleaned up its act a lot since then. Partly through the efforts of the Environmental Protection Agency. Partly through some half-hearted emission controls on cars (which were, by the way, easily subverted by the introduction of SUVs, which didn’t need to comply with the new standards). But the clean-up has mainly come from the fact that the US has moved a lot of its industrial production offshore, to the south and west.

Oddly enough, when we got to the UK, there was also a haze in the air. But this was the golden haze of a drought summer, caused not so much by industrial pollution, as by dust and pollen thrown into the atmosphere, combined with smoke from the inevitable fires.

In general terms, the northern hemisphere has more atmospheric pollution than the southern, as the result of 250 years of industrial production. There is a perpetual haze in most northern places, to a greater or a lesser extent, ranging from the blanketing smog from forest fires in South Asia, to the industrial smog of China, to the lighter fumes from cars and trucks in the “post-industrial” countries. Whenever I return to New Zealand from the north, I am struck by the clarity of air in the south.

For the avoidance of doubt, I am not saying that the northern hemisphere has air pollution and the south does not. Many places in the southern hemisphere have their own local problems, such as Santiago in Chile[viii]. But the preponderance of air pollution is linked to the preponderance of population and industrial production in the north.

Two of the Planetary Boundaries relate to these forms of air pollution.

Planetary Boundary 8 – atmospheric aerosol loading – unknown: The first Boundary is “atmospheric aerosol loading” – droplets or particles in the atmosphere. These are primarily from industrial production. They actually have a cooling effect, but also cause chemical changes to the air. The framework identifies this as important enough to be a “Planetary Boundary”, but cannot quantify either its state or the likely boundaries, except in local case studies.

One dilemma that has to be faced is that atmospheric aerosols cause “global dimming” (which has the cooling effect referred to above). This means that if we reduce the level of aerosols in the air (through, for example, cleaner industrial production), we will also accelerate global warming. Again, no one is sure of how strong such an effect will be.

Planetary Boundary 3 – stratospheric ozone depletion – green zone: You will probably be familiar with this Boundary. A massive hole in the ozone layer rapidly opened up over the Antarctic in the 1970s and 1980s. It turned out to be caused mainly by chloro-fluorocarbons (CFCs), the chemicals used in refrigerators and aerosols.

The ozone layer screens out much of the sun’s ultra-violet radiation. If unchecked, this hole would cause great damage to life on Earth, through such things as skin cancers and genetic damage. The layer is of such significance to life that it is treated as another of the Planetary Boundaries.

And it gives us one of the few success stories where the environment, quality of life and human survival have triumphed over greed and consumption. The Montreal Protocol of 1987 capped, and then banned, the release of CFCs, with the result that the hole in the ozone layer has stabilised, and is even showing signs of closing.

One of the main reasons for this success is that the economic disruption caused by the rapid exit from CFCs was fairly minor. Alternative technologies were available, and the economic scale of the transition was not vast. So it was more comparable to the disruption of the watch and camera industries by digital technologies than to the impending and essential abandonment of fossil fuels in favour of renewable energy production.

The control variable is the concentration of ozone in the stratosphere, and the safe Boundary is no more than 5% reduction in this level from pre-industrial times. This Boundary is now only transgressed over the Antarctic during the southern spring (the actual “ozone hole” itself).

We’ve done a quick tour through the state of the land, water and air. And in doing so we had a quick look at the state of the forests, the plants and the fishes. Now it’s time to turn to the animals, birds and insects which inhabit the land and the air.